The General Fix

Since WordPress blocks are still changing, a general idea for fixing conflicts with plugins when reusable blocks aren't working:

  1. Back up your WordPress database (I used the "UpdraftPlus - Backup/Restore" plugin)
  2. Reset/wipe your database (I used the "WP Reset" plugin)
  3. Restore the backup from step 1, but *exclude* suspected or all block-specific tables in the database
  4. Re-build and save your reusable blocks as needed

Background

If you're like me, you started adding blocks awhile ago, but that's something WordPress has been changing a lot still, and this affects plugins, in turn.

One of my WordPress sites had database problems: the REST API wasn't right, the WP Admin bar wasn't showing on pages, and, worst of all, I was unable to successfully update pages with the page editor.

Screenshot WordPress Editor Updating
WordPress Page Editor stuck 'Updating...'

I was having a lot of trouble with WP reusable blocks also. They wouldn't load properly in the editor, and I couldn't update them, because page save never completed.

The SSL plugin also reset for no reason, so I had to go through that wizard again.

The Fix - Specific to Wordfence Security plugin

On a hunch, I reset the entire database and then re-loaded the backup *excluding the 2 Wordfence Security tables about WP blocks* and everything is working again. *phew*

If your WP reusable blocks are mixed up, you use the "Wordfence Security" plugin, and you can't save pages, here is how to use this *one* possible solution (it worked for me):
*Note: you will need to re-create your reusable blocks

  1. Back up your database (I used the "UpdraftPlus - Backup/Restore" plugin)
  2. Reset/wipe your database (I used the "WP Reset" plugin)
  3. Restore the backup from step 1, but *exclude* these tables: <prefix>_wfblockediplog and <prefix>_wfblocks7

Now you can re-build and save your reusable blocks.